Cognitive scientists once spurned the dog as too domesticated to study.
But now many are leaping at the chance to use man’s best friend to help
understand how social cognition evolved
BUDAPEST—In 1994 when Ádám Miklósi,
then a young ethologist at Eötvös Loránd
University in Budapest, learned that his lab’s
director planned to switch the team’s
research from f ish to dogs, he couldn’t
believe it. “ ‘My god, are you crazy?’ That’s
what I thought, although I didn’t say it,” says
Miklósi, who now directs the university’s
highly regarded dog cognition lab. “None of
us were happy about this.” At the time, scientists who studied animal behavior and cognition were busy investigating a variety of
species, including ants and dolphins, but
they shunned dogs because they thought the
animal’s domestication, and the bond
between human and dog (Canis familiaris),
precluded objective study. In fact, lab director Vilmos Csányi’s interest had been spurred
by his admiration for Flip, a mixed-breed dog
he had found in the woods and adopted. “He
would tell us some crazy story about Flip and
say, ‘Now, devise an experiment to find out
why Flip can do that,’ ” says Miklósi.
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Fifteen years later, in the wake of dozens
of provocative studies from the Hungarian lab
and a few others, dogs are fast becoming the
it animal for evolutionary cognition research.
Well-known cognitive scientist Marc Hauser
of Harvard University announced in February
that his lab was switching from cottontop tamarin monkeys
to dogs. Around the
world, from Australia
to Japan, other dog sciencemag.org
Podcast interview
ethology and cogniwith author
tion labs are either Virginia Morell.
fully under way or in
the works. Last year, Miklósi’s group held the
first-ever dog cognition conference; a second
is planned for July 2010 at the Clever Dog Lab
and Wolf Science Center (WSC) at the University of Vienna. Last month, an issue of the
journal Behavioural Processes was devoted to
the dog, with 12 papers from behaviorists and
ethologists analyzing everything from canine
barking to dogs’ guilty faces. And this week,
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CREDIT: ENIKO KUBINYI
Going to the Dogs
researchers explore how dogs evolved their
social smarts in a PloS ONE paper comparing
how young and mature dogs and wolves follow human cues. Even the shape of dogs’
faces is being studied: Scientists in Miklósi’s
lab reported 24 July in the journal Behavioral
and Brain Functions that dogs with rounder
faces, such as pugs, are better at following
people’s cues than breeds with longer noses,
indicating that we’ve selected puglike breeds
not for their baby faces but for their ability to
look us in the eye.
Our canine pals, researchers now say, are
excellent subjects for studying the building
blocks underlying mental abilities, particularly those involving social cognition. The
special relationship with humans that once
disqualified dogs from research is now seen
as worthy of study in its own right; some
researchers see the dog as a case of convergent evolution with humans because we
share some similar behavioral traits. And
because all dogs are descended from gray
wolves (C. lupus), they can reveal how
domestication has altered a species’ mental
processes, enabling the dog to survive in its
new habitat, the human home. “They’re a
natural experiment,” says Josep Call, a comparative psychologist at the Max Planck
Institute for Evolutionary Anthropology in
Leipzig, Germany, who studies cognition in
dogs, wolves, and great apes.
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Leading the pack. Cat lover Ádám Miklósi works
with dogs in his Budapest lab.
CREDITS (TOP TO BOTTOM): FRIEDERIKE RANGE; ISTOCK PHOTO
Miklósi, Call, and others even argue that
dogs may teach us more about the evolution
of some aspects of our social mind than can
our closest kin, the chimpanzee, because
Fido is so adept at reading and responding to
human communication cues. But not everyone agrees. “Completely wrong,” says Clive
Wynne, a psychologist at the University of
Florida, Gainesville, who argues that the
skills dogs share with humans are a matter of
learning rather than evolutionary change.
But Wynne, who edited the special Behavioural Processes issue, agrees that dog
ethology and cognition are hot f ields.
“There’s no other species on the planet that
triggers so many questions and debate, and
no animal that we have a more intimate relationship with, than the dog.”
Researchers have also worried that dogs
are too aware of human cues and so would
defeat most experimenters as did Clever Hans,
the horse once celebrated for tapping out
answers to math problems—and later shown
to be closely watching his owner for subtle
clues to when he should stop tapping. To prevent this, dog ethologists carefully monitor
testing methods, generally videotape experi-
us? That’s the kind of thing that dogs can
help us investigate.”
And despite the concerns, dogs in fact have
many advantages as cognitive research subjects, say Miklósi and others. Dogs are willing
and cooperative, and they enjoy being with
people and following their commands.
The dog’s genome has been mapped (Science,
21 September 2007, p. 1668), opening up the
possibility of linking behavioral traits to specific genes.
To cap it all off, dogs are much
less expensive to study than
most laboratory animals,
largely because most dog labs
follow the model of Miklósi’s
Family Dog Project and don’t
actually house dogs (which
also helps keep animal-rights
activists at bay). “All you need
is an empty room for a dog
lab,” says biological anthropologist Brian Hare, who is
busy setting up such a room at
Duke University in Durham,
North Carolina. “Then you ask
people if they’d like to have
their dogs take part in a cognitive experiment. Everybody
knows their dog is smart, and
the next thing you know, you
have 1000 dogs to test.”
“It’s like Drosophila
genetics,” adds Hauser. “Why
stop at 1000; why not have
10,000? It’s a huge change
from simply studying 30
tamarins.” Thus dog research
can be replicated—a tall order
when working with some
other animals. “Let’s face it:
No one is going to be able to
replicate my bonobo studies,”
says Hare, “because there
isn’t another population of 60
bonobos to test.”
Real animals?
Dogs weren’t always viewed
this way. Although Charles
Darwin and Ivan Pavlov considered dogs fine subjects for
studying evolution and behavior, cognitive scientists and
ethologists placed dogs in a
kind of research purgatory for
many years. In the 1970s, when
cognitive ethologist Marc
Bekoff of the University of
Colorado, Boulder, launched a
study of dog play behavior,
many of his colleagues sniffed
at the idea. They said “ ‘Why
don’t you study real animals?’”
he recalls. Domestic dogs were
considered artificial and therefore “not worthy of study”—a
concern that many researchers
still have. Domestication
makes dogs “less useful for
investigations on the evolution
of cognition,” says Nicola
Reading minds
Clayton, who studies bird
Into the canine mind. Researchers are giving dogs touch-screen tests (above)
behavior at the University of
With so many dog labs joining
and investigating that guilty look to understand how dogs think.
Cambridge, U.K., “because
the pack, new and provocative
you can’t look for the ecological effects, for ments, and use various techniques, including findings are emerging. For example, etholowhat originally drove intelligence in dogs.” blindfolding human testers, to make certain gists have shown that dogs, even as puppies,
Also, “the investigator has no control over the they are not inadvertently giving clues.
can follow human pointing gestures to find
nurture side: how owners feed, train, or treat
Dogs were also deemed to have another hidden food, something difficult for chimtheir dogs,” says primatologist Frans de Waal problem: Their brains are 25% smaller than panzees to do (Science, 22 November 2002,
of Emory University in Atlanta. That “intro- those of their wild ancestors, wolves. “Most p. 1634). The experiments suggest that dogs
duces unknown variables we would normally people thought—and some still do—that can read human intentions, implying that the
not accept in animal behavior research.” Still, dogs were therefore not as smart as wolves,” two species share information via a complex
Clayton and de Waal support the move to says Call. But “brain size is not everything. form of communication. Even more controdogs. When it comes to dogs, “the pros out- … How did domestication change wolves versially, the discovery suggests to some that
weigh the cons,” says de Waal.
into dogs? Is it similar to what happened to dogs may understand what another being is
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ment. What people see in dogs is the anticipation of punishment.” In humans, says
Tomasello, that anticipation is regarded as a
“precursor to guilt.”
Indeed, some researchers think that the
evolutionary steps gray wolves took to live in
human society may in some ways mirror the
transition from ape to human. The loss of fear
and aggression toward others and the emphasis on cooperation rather than competition are
steps that early hominids must also have
taken as they organized into groups, although
for dogs the change also required evolving a
deep attachment to an entirely different
species. “Dogs have lived with us for at least
10,000 years, and they’ve evolved to fit into
our social world, so they’ve developed some
social and behavioral skills strikingly like
ours. It’s a case of convergent coevolution,”
says Call.
Wynne’s having none of the coevolution
argument, however. “Dogs and wolves are
still the same species,” he says. “They still
interbreed, and so any changes in the dog’s
brain are a matter of degree rather than
kind.” And he is skeptical of some of the
claims regarding dogs’ abilities, particularly
those that suggest superior mind-reading
skills as compared with wolves. “Sometimes
I feel that I’m always running after other
people, stomping out the f ires they’ve
started” with claims of dogs’ advanced abilities, he says. He argues that the Border collies with fat vocabularies are merely “conditioned” and that their talent for picking up
human sounds is not at all comparable to
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thinking, a sophisticated talent called theory of mind that many researchers think
even chimpanzees and preverbal human
infants lack.
Dogs can also imitate a human’s actions
on command (“Do as I do!”), much like children playing “Simon Says,” according to
studies done by Miklósi’s colleague József
Topál and his team at the Institute for Psychology at the Hungarian Academy of Sciences in Budapest. That’s an indication that
dogs are strong social learners, something
still debated for chimpanzees. “They’ve been
selected for this sensitivity and to cooperate,”
says Miklósi, who confesses to being a cat
person and has never owned a dog. Dogs can
also use computer touch-screens to demonstrate some glimmerings of abstract thought,
such as the ability to form a concept. For
example, dogs were able to select color photographs of other dogs instead of landscapes,
choosing with a quick nose-touch to the
screen. Pooches can follow human rules, a
social skill that helps strengthen group bonds;
they have a sense of fairness; and some
canine whizzes—all Border collies so far—
have vocabularies of several hundred names,
suggesting an ability to learn words that some
say resembles that of infant children. Also
like human toddlers, dogs willingly imitate
another’s actions, even if these don’t always
make sense, an ability that makes
it easy to learn from others. In
short, dogs are skilled at cognitive
tasks, especially social tasks
requiring cooperation and sharing information to achieve a goal.
Sometimes these advanced social skills
lead dogs to behaviors and emotions that
seem very humanlike. But are they? Take the
“guilty look” every dog owner knows. While
cameras rolled, Alexandra Horowitz, an animal cognition researcher at Barnard College
in New York City, had 14 owners show their
dogs a tasty treat and tell them not to eat it.
But when the owner left the room, Horowitz
either gave the dog the forbidden food or
removed it, making it impossible for the
pooch to misbehave. Later, some owners
were told that their dogs ate the treat, even
when they had not. “It didn’t matter if the
dogs had done the right thing. If they were
scolded, they showed that guilty look,” slinking away with their heads drooping and ears
flattened, says Horowitz, whose work is published in the July issue of Behavioural
Processes. “And the dogs who showed the
most ‘guilt’ were the ones that hadn’t disobeyed. We’ve trained them to give us that
look” in response to our anger. “The guilty
look is not necessarily a reflection of anything they have done,” she says. Adds
Michael Tomasello, a comparative cognition
researcher also at the Max Planck Institute in
Leipzig: “Guilt involves a moral dimension,
which dogs very likely don’t have. But by
showing guilt, we may lessen our punish-
CREDITS (TOP TO BOTTOM): COURTESY OF FRIEDERIKE RANGE, WOLF SCIENCE CENTER; ENIKO KUBINYI
Raised by humans. Wolf cubs raised like dog puppies (top) play with dogs and grow up to be
as good as adult dogs at following human pointing cues in experiments.
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CREDIT: BEA BELÉNYI
From wolf to dog
Despite Wynne’s concerns, for many the evolutionary process that produced the dog is fertile ground for research. Most agree that
domestication changed the dog dramatically,
turning it into a creature who yearns to be
with a species other than its own. Researchers
hypothesize that this happened because
humans selected dogs for their ability to
socialize and to form strong attachments with
people. Indeed, experiments in Miklósi’s lab
have shown that 4-month-old puppies in a
choice test always preferred a human companion to a dog. Young wolves showed no
preference. “Domestication changed” the
dog brain, “making it more attuned to human
social signals,” says Miklósi.
To test that idea, scientists have examined how well dogs and wolves can pay
attention to human pointing cues and hold
eye contact with people. (Wild wolves, like
many wild mammals, are reluctant to make
eye contact, perhaps because in many
species staring is a threat.) Previous pointing
studies had mixed results: In the original
tests, dogs proved to be superior to wolves
(and chimpanzees) in following a human’s
finger to a bucket that held a hidden food
treat. Many researchers interpreted this as an
indication of a genetic component to this
skill, one favored by domestication. But
later tests complicated the issue: In another
study using a different method, wolves actually topped the hounds.
To clarify the question of just what wolves
can do, Márta Gácsi of Miklósi’s lab and her
co-authors hand-raised gray wolves much as
pet dogs are raised, as they report this week in
PLoS ONE. Then they gave carefully
designed pointing tests to wolves and dogs
of different ages. Intriguingly, 8-week-old
and 4.5-year-old wolves were as good as the
dogs at following the human pointing cues
t o h i d d e n f o o d. B u t t h e 4-month-old
wolves failed. “They were struggling and biting; they were just too busy doing other
things,” says co-author Friederike Range of
WSC. In addition, in contrast to the young
dogs, the young wolves had trouble making
eye contact with their humans. “They are on a
different developmental path from dogs,”
perhaps because ultimately dogs “must live
in our world and obey our rules. They have
to learn many of the same things that children learn,” says Range. And so it behooves
dog puppies to look into their owners’ eyes
and pay attention.
“The study is a slam dunk,” says Hare,
who says it shows “once again that dogs and
wolves are different.” He and others say that
the study reveals that dogs are born ready
and willing to work with people, whereas
wolves face a long learning curve before
they can accept two-legged creatures as
social partners. But because the wolves can
learn over their lifetime to follow our cues,
the study also points out how difficult it is to
“unravel genetic factors” from socialization
and training, notes de Waal.
“We have so many questions to ask,” says
Miklósi. “What do dogs understand about
verbal commands? How do they recognize
their owners? What do they think of as sig-
warnings or to protest. In contrast, dogs bark
for many reasons, says Miklósi. “They
‘invented’ barking,” as a means of communicating to us as much as to other dogs, and
they “can modulate the frequency and
pulse” to signal fear or that they are feeling
lonely or playful. In a previous study, Peter
Pongrácz in Miklósi’s lab showed that
humans can readily identify the differing
barks of a lonely, fighting, or playing dog.
“That means that a dog’s bark is often
directed at us to convey the dog’s inner
state,” Pongrácz says, an ability that has
likely come about because dogs live with a
talkative species.
As part of his ongoing, as-yet-unpublished
study of dog-human communication, Tamás Faragó,
one of Pongrácz’s graduate
students, covered a small
cage with a cloth and
placed a large, tempting
bone close by. Kope, a
bright-eyed Cairn terrier,
trotted in off-leash with his
owner, spied the bone, and
made a beeline for it. But
just as Kope reached the
bone, Faragó played a
recorded growl, and the
dog froze in place. “That’s
a food-guarding growl,”
Faragó whispered. “As
soon as a dog hears that, he
knows he better leave that
bone alone.” When the
unseen dog growled a second time, Kope, looking
unnerved, ran halfway back
to his owner, wagging his
tail. He peered up at her
face, then looked back over
his shoulder at the bone.
“He’s asking for help,”
Faragó explained. “ ‘Come
on, Mommy, help me get
The changeling. Domestication turned gray wolves into cooperative that bone. Let’s do it
together.’ ”
dogs attuned to human social cues.
That, say Miklósi and
nificant in their environment? What does a others, is what lies at the heart of dog cognidog understand about human relationships; tion: their strong desire to work with and for
what does he know about your state of us, and their ability to communicate with us
mind? And then we should ask the wolves without language. “That’s the one thing all
the same questions.”
of us doing dog research must never forget,”
On one recent day, dogs and their owners says Tomasello. “Dogs are collaborating
stopped by to join in an experiment at the with us; they aren’t doing this with other
Hungarian lab, investigating how dogs dogs.” Unraveling how that collaboration
respond to certain growls, part of a larger came about—how it turned wolves into
study aimed at understanding how dogs’ dogs, and humans into dog lovers—is like a
barks and growls have changed from those good bone: one well worth digging for.
of wolves. Wolves bark, too, but only as
–VIRGINIA MORELL
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how children learn words. “If they were
really like children, they’d be learning hundreds of words a day,” he says.
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